The present invention relates to a device for guiding a web of flexible film that has been folded back on itself, particularly, although not exclusively so, for use in an apparatus for manufacturing pouches or bags containing a perfusion liquid.
There are known machines for the manufacture of pouches or bags from flexible plastic film. Specifically, there are known machines for the manufacture of pouches or bags from a thermoplastic film. These machines include a series of stations at which the film is treated in succession. Generally, the film is unwound from a winder, then perforated. Perpendicular to the perforations, ports or fitments are sealed by a welding head. The film is then shaped in a film-shaping device. The film-shaped device is designed to fold the film back on itself, for the purpose of creating an edge to edge seal. Once sealed edge to edge, the film forms a tube that is then sealed in a transverse direction, at regular intervals, in order to form individual pouches or bags. Those pouches or bags then are filled prior to the creation of a second transverse seal that forms the pouch or bag.
The present invention more particularly relates to the step of the process that immediately precedes the creation of the edge to edge seal. When the film is folded back on itself as it passes through the shaping device, the two edges of the film may not be precisely juxtaposited. If the shift between the edges is too great, the edges are not sealed together when they pass through the sealing device.